______ is an electromagnet with its core in the form of a close magnetic ring.

A. S olenoid

B. Paraboloid

C. Toroid

D. Cycloid

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  1. What determines the value of the temperature coefficient of resistance of a material?
  2. The B-H curve for ________ is a straight line passing through the origin.
  3. A magnetic circuit carries a flux iin the iron part and a fluxgin the air gap. What is the leakage coefficient?
  4. Cobalt is an example of a ______ material.
  5. The electric potential at a point in air due to a charge is 21 V. If the air is replaced by a medium…
  6. Hysteresis loss can be reduced by one of the following.
  7. The contribution to the ionization in an ionization chamber by electrons liberated from t he walls.
  8. What is the SI unit of conductivity?
  9. If the number of valence electrons of an atom is exactly 4a then the substance is called
  10. The magnetic energy stored in an inductor is ______ current.
  11. The reluctance of the magnetic circuit is ________ relative permeability of the material comprising…
  12. Who developed the electromagnetic theory of light in 1862?
  13. Which of the following magnetic materials can be easily magnetized in both direction?
  14. The diameter of a hydrogen atom is approximately ______ cm.
  15. What is the other name for dielectric strength?
  16. Two similar polesa each 1Wba placed 1 m apart in air will experience a repulsive force of
  17. Hipernik is an alloy containing __________ iron and __________ nickel.
  18. The electric flux density is a ________ quantity.
  19. Which of the following is used by temporary magnets as the magnetic material?
  20. The ratio between the intensity of magnetization produced in a substance to the magnetizing force producing…
  21. A test charge means a charge of
  22. The customary energy unit in atomic and nuclear physics is
  23. Electronic current in a wire is the flow of ____________ electrons.
  24. At/m is a unit of
  25. If the number of valence electrons of an atom is more than 4a the substance is called
  26. What is the SI unit of conductance?
  27. The unit of electrical energy is
  28. The property of a material which opposes the creation of magnetic flux in it
  29. Lenz' law states that the direction of the induced emf and hence current
  30. If the right handed bottle-opener cork screw is assumed to be along the conductor so as to advance in…